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In the present experiment, a study was conducted to investigate the effect of conservation treatment of an Arabic manuscript on its chromatic characteristics. For this purpose, extremely valuable, unrestored manuscripts (18 - 19th century) were selected from the archives of the National Library "St. St. Cyril and Methodius", on which spectrophotometric chromatic characteristics were measured. The research was conducted at the restoration center of the National Library. The following processes were applied to the manuscript: mechanical cleaning and deacidification. Measurements of color characteristics were taken indifferent parts of the manuscript after each stage of the treatment: before treatment, after mechanical cleaning, after deacidification. The following parameters - CIE Lab, CIE Lch, ΔEab, ΔE2000, ΔL, Δc, Δh was calculated. Based on the results obtained, the changes and effects of each of the chromatic parameters were determined. [ABSTRACT FROM AUTHOR]

For many centuries paper has been the mainstay material for recording cultural achievements around the world. Paper is produced mainly from cellulose with small amounts of organic and inorganic additives, which allow its identification and characterization and can contribute to the decomposition of the paper. Spectroscopic technique is a powerful tool for examining the constituent elements of paper documents to establish their identification and their state of degradation. This review describes the application of selected spectroscopic technique used to characterize paper and inks. Spectroscopic technique that has been reviewed include: Infrared spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray fluorescence analysis, Inductively Coupled Plasma Mass Spectrometry, SEM-EDX, energy dispersion X-ray fluorescence. [ABSTRACT FROM AUTHOR]

This paper presents the research of the heat treatment effect on printed textile substrates. The samples used in the experiment are printed employing Epson Stylus Pro 4880 inkjet printing machine and Epson Ultrachrome inks. Two different types of textile materials are used as printing substrates. The composition of the materials is identical, but they differ in respect to their fabric weight and thread count. The samples are exposed to two heat treatments after printing. The results obtained provide the conclusion that the heat treatment affects the color change, while the print uniformity remains unchanged to some extent. [ABSTRACT FROM AUTHOR]

Flexographic sleeves are made using various materials, including a sub-group with extremely durable polyurethane foam shock-absorbing layer. During exploitation, the sleeves are exposed to cyclic dynamic loading, and the flexographic printing process is highly sensitive to the changes in pressure. Deformation of printing elements occurs due to the almost two times higher residual strain of the exploited sleeves. Changes in the residual strain induce occurrence of the hysteresis losses, which lead to heat generation. The forces impacting the material are not strong enough to induce permanent deformation in the microstructure. Therefore, the leading cause of the change lies in the molecular structure of the parent polymer of the polyurethane foam cell walls, whose resilience is declining. The thickness of the exploited sleeves tends to be around 8 % lesser. In addition to high-frequency cyclic loads during printing, the adhesive layer of self-adhesive sleeves undergoes reduction in the share of acrylates, phthalates and rosin, thereby reducing the adhesive strength and the force needed to initiate the de-adhesion by half. The knowledge of mechanisms of change in certain characteristics of the sleeves enables predicting their service life and increasing the stability of the printing process through possible corrections of other process parameters. [ABSTRACT FROM AUTHOR]

The main goals of this research are investigation and determination of color balance failure (color inconstancy) of offset printed images expressed by color difference depending on the material used and different standard illuminant conditions. For the experiment, we chose three of the most commonly used in practice illuminants -- CIE D50 natural horizon daylight with color temperature 5003 K; CIE F2 cool white fluorescent, 4230 K; CIE A typical Tungsten-filament lighting, 2856 K. A special test form that has been used contains different control strips and measurement components include test chart TC6.02 with about 1000 color patches with different percent combinations of cyan, magenta, yellow and black. The paper, printing inks and printing presses employed in the experiment are some of most commonly used in practice for producing high quality color reproductions. A series of colorimetric and densitometric measurements were performed for different combinations of C, M, Y, K in single, double, triple and quadruple overprint for high tones, middle tones and dark tones. For estimating color balance failure for all the above mentioned measurements there have been calculated the color difference ΔEab* and CMCCON02 depending on standard illuminants CIE D50, F2 and A. For the first time via experimental research in real production conditions (for offset printing method), 3D and 2D presentations and comparison of color gamuts and color gamut volumes for different illuminants were made. According to the results, CIE A has the biggest color gamut volume and CIE F2 -- the smallest one. The results obtained are important from scientific and practical points of view. For the first time a methodology is suggested and implemented for examination and estimation of color shifts by studying a big number of color changes in various ink combinations for different illuminants. [ABSTRACT FROM AUTHOR]